Process of making glass letter plates



Jun 15,1926; 1,58%,580

A R. F. HANCOCK PROCESS OF MAKING GLASS LETTER PLATES Filed Feb. 5, 1925 JW ZZW fj/mmdz- Patented June 15, 1926..

UNITED STATES PATENT OFFICE. I

RAYMOND I. HANCOCK, OI. MARION, INDIANA, ASSIGNOR OF ONE- HALF TO JAMES BOYCE, F LAKETON, MICHIGAN, AND ONE-HALF T0 HARRY ANDERSON, OF

MARION, INDIANA- PBOCESS 01 MAKING GLASS LETTER PLATES.

Application nled February 5. 1925. Serial No. 6,951..

This invention relates to the manufacture of embossed letter plates such as are used in the construction of electric signs. The object of the present invention is to 5 improve upon the method disclosed in Patent N 0. 1,465,507, granted August 21, 1923, to Harry F. Anderson. The Anderson process-consists in rollin out a sheet of glass upon a pallet, and, while the sheet is still plastic, transferring the sheet from the pallet to a die plate having depressions therein corresponding to the shape of the signcharacter to be produced. Fluid pressure is then employed to force into said depressions the glass plate is produced having a concavoconvex sign character. In this method of making embossed letter plates, the side of the plate which is in contact with the die plate loses, or fails to develop, the desired.

glazed surface; and it is consequently necessary to subject the letter plate to a further operation in order to impartthereto the glaze which it must have in order to be an eflicient and marketable article. -T he object of my invention, more particularly stated, is to improve upon the beforementioned method so as to impar't to both surfaces of the letter plate the necessary refund to.

In the accompanying drawings, Figure 1 is a fragmental elevation illustrating an apparatus which may be employed in carrying out my-p'rocess; 1

Fig. 2 is a fragmental elevation of an apparatus'for applying fluid pressureto the plate in carryingout tlie final step of (the 40 process.

Fig.3 1s a view of a sign-letter late.

In the drawing, 1, denotes a ta le of any desired form and size, with ra mold or. die plate 2 mounted therein. The upper surface of the'die plate has depressions 3 therein cor-" responding to the shape of the letter or other si character to be formed. r

- Thstead of rollingl plastic glass into a sheet upon a allet and t on transferring the sheet 'to the 10' plate,-I deposit the sheet u n the die plate asthe sheet is being form The means employed in carrying out this portion [of the process comprises two rollers t end' I l 1 overlying portions of the sheet, whereby a glaze without the further operation above both sides of the sheet. The

mounted on parallel axes in a suitable carrlage (not shown), 'said carriage being mounted in such a way that it may be drawn across the table. The rollers 4 and 5 are spaced'apart a distance equal to the thickness of the sheet of glass to be formed, and the roller 5 is spaced a similar distance from -the top of the table andthe die plate. The before-mentioned carriage also supports a hopper 6 for the molten glass, the hopper bemg arranged to discharge its contents between the rollers 4 and 5. The apparatus is so arranged that as the carriage is moved across the table the rollers 4 and 5 rotate in the directions indicated by the arrows, whereby the-glass flowing from the hopper is formed into a sheet a which is deposited directly upon the top of the die late 2. The rollers 4 and 5 become heated y reason of the heat of the molten glass, but they may be further heated by any suitable means, if so desired. g

' The lastic sheet of glass having been thus forme and laid upon the die plate, fluid pressure is applied to force the sheet into conformity with the die plate. Any suitable 'means may be employed in carrying out this step of the process, the means herem shown comprising a hood 7 arranged to be lowered onto the table 1 so as to enclose the glass sheet. Compressed air or other pressure fluid is supplied to the hood through a pipe 8. The pressure of the fluid against 1: e

glass sheet causes the portions thereof which overlie the depressions of the die plate to be forced down into sald depressions,-whereby a concavo-convex sign character is formed in the sheet of glass. Thecompleted letter plate'is then removed from the die plate 2. The rolling out of the glass between the rollers 4 and 5 produces a glazed surface on laze on the lower side of the sheet is not estroyed by the deposition of the sheet; on the die plate, and hence the necessity of imparting a glaze to the embossed outer side of the finished letter plate is obviated, with a consequent material reduction in the cost of the finished product.

' I claim as my invention:

1. The method of producing concavo-conve g a s gnwharacter' p ate hich consists in rolling a mass of molten glass into a sheet ti'uding a sheet of glass, laying said sheet between two rollers, depositing the sheet didirectly upon the surface of a die, and reetly upon a die plate, and exerting fluid exerting fluid pressure against the sheet to 10 pressure against the sheet to force the latter force the latter into conformity with the die.

into conformity with the die plate. In testimony whereof, I have hereunto af- 2. The met 0d of producing concavofixed my signature. I convex sign characters which consists of ex- RAYMOND F. HANCOCK. 

